This is a Phase II randomized, double-blinded, controlled study in up to 700 males and non-pregnant females, 19 to 64 years old, inclusive, designed to assess the safety, reactogenicity, and immunogenicity of a monovalent influenza A/H7N9 virus vaccine administered at different dosages (3.75, 7.5, or 15 mcg of HA/0.5 mL dose) given with and without MF59 adjuvant and without adjuvant (15 mcg of HA/0.5 mL dose and 45 mcg of HA/0.75 mL dose). Subjects will receive two doses via intramuscular injection, approximately 21 days apart. Safety, reactogenicity, and immunogenicity data will be collected at standard time points with safety follow-up to continue through one year post dose 2. The duration of the study for each subject will be approximately 13 months.